The present invention relates to a network of programmable equipment, and, more particularly, to a shared operating unit for use with multiple controllers on the network of programmable equipment.
For industrial equipment, particularly robots, pendants have been used to facilitate manual motion, teaching, maintenance and testing programs. The development of the pendant is a product of a historical need to xe2x80x9cteachxe2x80x9d movement to the robot, as opposed to numerically programmed machine tools wherein movement was programmed from blueprints. For robots, the data was too complex to be expressed in blueprints because the movement data involved the relationship between parts, between a part and a fixture, and between fixtures. While cell layout by computer and accurate interprocess motion definition through off-line programming is a relatively recent development, the first robot had to be programmed by showing it the specific intracell relationships. Towards this end, the pendant was developed for directing manual motion of the machine, and recording and modifying the motion data so that the machine could be used as a measuring device. Further, the pendant was a source of program generation and test playback for the machine motion. Over time, the pendant also became a source for many maintenance-related operations.
Using a pendant to direct manual motion of a robot is akin to the handwheel that has been used to manually move machine tools around. For pendants, buttons and joy sticks have evolved as the basic manual motion control mechanism. Further, the ability to manually move machines is not simply a teaching feature, but also a safety and recovery feature. That is, manual motion is employed to bring machines to safe positions during start up and maintenance operations and to recover from program failures. Further, the use of a pendant for recording or modifying movement data for subsequent playback permits the robot to be used as a measuring device. This sort of teaching function evolved as an accurate way to get the robot to a particular point in space and then record where the robot xe2x80x9cthinksxe2x80x9d it is.
Because of a need to be near the robot in order to visually verify the correct operation of the process being facilitated by the robot, program testing is quite often done at the pendant. This has resulted in the evolution of teach-pendant-based languages that span nearly all application requirements, such that most functions can be done from the pendant. As a result of the heavy reliance on the pendant for most robot-related functions, most maintenance-related operations and set-up operations similarly occur at the pendant to avoid the use of a second interface. Although theoretically these functions could be done elsewhere, such as at the operation control panel for each robot, historically these functions have been incorporated into the pendant. Accordingly, as more and more functionality has been added to the pendant, the cost to manufacture it increased significantly.
As a result of the evolution of pendants, a typical network of programmable equipment including robots has a pendant for each robot, and many include an operator control panel in addition to the pendant. The pendant is used for the manual motion, teaching, programming and maintenance functions discussed above. The pendant is usually tethered to a controller for the particular piece of programmable equipment. Because the pendant is a high cost item, a simple way to reduce costs would be to eliminate the pendant. But given the background of pendant evolution, and the reliance on the pendant for manual motion, teaching, programming, and maintenance functions, elimination is not realistic. Accordingly, it is desired to provide the use of a pendant for each piece of programmable equipment, such that any of the traditionally relied on pendant functions may be employed, while reducing overall costs.
Sharing an operating unit, or a plurality of operating units, each having pendant functions, among a network of programmable equipment including robots overcomes the limitations of the prior art and helps reduce overall cost by providing more efficient use of the xe2x80x9cpendant,xe2x80x9d or shared operating unit. Further, by providing advanced functionality in the shared operating unit and a control handle to which it is selectively coupled, the functions of the operator control panel can be replicated, therefore rendering the conventional operator control panel extraneous.
In a network of programmable equipment including robots, wherein each piece of programmable equipment includes its own controller, the shared operating unit selectively couples to the control handle, which itself is coupled to a particular controller to provide communication between the shared operating unit and the controller. When the shared operating unit is connected to the control handle, the operating unit is able to provide conventional pendant functions for the particular piece of programmable equipment through the controller. Further, the control handle itself includes at least some minimal functionality operable when the shared operating unit is not coupled to it. Optionally, between the control handle and shared operating unit, all of the operator control panel functions are provided. Moreover, additional functionality can be provided in the shared operating unit, adapting it for stand-alone use and network communication, whereby programming, testing, and monitoring of any networked industrial equipment can be accomplished from a remote network location.
In a version of the invention, for safety and practicality, when connected to the control handle, the shared operating unit is able to provide certain functions that it is not able to provide when unconnected. Further, the control handle can be either physically connected or wirelessly connected to a particular controller and/or a network hub. Where physically connected, the communication is preferably via a serial bus. Where the connection is wireless, a wireless application protocol is preferred.